Results 41 to 50 of about 5,163,973 (225)
The location and kinematics of the emission line regions in Active Galactic Nuclei [PDF]
, 2008 This thesis contains the results from a study of the optical emission lines of various samples of active galactic nuclei (AGN). We have used three separate techniques to determine the precise kinematics and the relative location of the emission line ...
Mullaney, J R, Mullaney, J.R.
core
Principal Component‐Based Classification of Blazar Candidates of Uncertain Type in the 4FGL/LAT
Astronomische Nachrichten, EarlyView.ABSTRACT We adopted principal component analysis (PCA), linear discriminant analysis (LDA), and support vector machines (SVM), to study classification for a sample of 2708 Fermi blazars: 1142 BL Lac objects (BLLs), 759 flat spectrum radio quasars (FSRQs), and 807 blazar candidates of uncertain type (BCUs).
Wen‐Xin Yang +13 more
wiley +1 more source
Optical polarimetry studies of Seyfert galaxies [PDF]
, 1999 Optical imaging polarimetry has been performed on seven nearby Seyfert galaxies, three with face-on and four with edge-on host galaxies of various morphological classifications.
Felton, Michelle Ann
core
Spatially resolved spectroscopy of faint star-forming galaxies & their environments in the high redshift universe [PDF]
, 2011 This thesis is concerned with the spectroscopic observations of distant galaxies, 1 < z < 5. The galaxies presented here are intrinsically faint such that their ux is dominated by ordinary star formation rather than galaxy-galaxy merging and/or ...
Hurley, Mairéad
core +1 more source
The Astrophysical JournalWe present statistics of z ∼ 6–9 galaxy outflows indicated by spatially extended gas emission and broad lines. With a total of 61 spectroscopically confirmed galaxies at z ∼ 6–9 in the JWST CEERS, GLASS, and ERO data, we find four galaxies with [O iii ] +
Yechi Zhang +7 more
doaj +1 more source
The Astrophysical Journal Letters, 2023 We present the first results on the spatial distribution of dust attenuation at 1.0 < z < 2.4 traced by the Balmer decrement, H α /H β , in emission-line galaxies using deep JWST NIRISS slitless spectroscopy from the CAnadian NIRISS Unbiased Cluster ...
Jasleen Matharu +16 more
doaj +1 more source
Direct SMBH Formation Driven by Runaway Stellar Collisions in Globally Unstable Stellar Systems
Astronomische Nachrichten, EarlyView.ABSTRACT The fueling problem addresses the ultimate fate of the reservoirs of gas and stars driven into the deepest gravitational potential wells of galaxies, thus it may contain the Universe's densest concentrations of gas and stars. This raises a key question: does the infalling material collapse directly into a supermassive black hole, or can it ...
Marcelo C. Vergara, Andrés Escala
wiley +1 more source
The Astronomical Journal, 2023 The Star Formation Across Cosmic Time (SFACT) survey is a new narrowband survey designed to detect emission-line galaxies (ELGs) and quasi-stellar objects (QSOs) over a wide range of redshifts in discrete redshift windows.
David J. Carr +4 more
doaj +1 more source
Spectroscopic Studies of Emission Line Galaxies [PDF]
Symposium - International Astronomical Union, 1994 Spectroscopic Observations were made to study 42 emission line objects. The analysis of these long slit spectra shows that 15 out of 42 galaxies are blue compact galaxies (BCGs). 21 of them are starforming or HII galaxies and 3 were found to be normal galaxies.
M. S. Chun +3 more
openaire +1 more source
Investigation on tunnel stability considering pipe‐roof support with transparent soil technology
Deep Underground Science and Engineering, EarlyView.This study integrates transparent soil technology, 3D reconstruction and numerical simulation to captures the full‐field deformation of shield tunnel instability. Results demonstrate that pipe‐roof support enhances stability via the “soil‐arching barrier effect,” effectively restraining failure wedge development by extending stress transfer paths ...
Zhi Jia +4 more
wiley +1 more source